﻿using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Demo05142
{
    class Stringutil
    {
        public static void Stringutil1(string a)
        {
            bool b = false;
            if (a == null || a == "" || a == " ")
            {
                b = true;
            }
            else
            {
                b = false;
            }
            Console.WriteLine(b);
        }

    }
}
